A bacteria population P(t) is modeled by dtdP=k(1200−P), where t is measured in hours. At the instant when the population is 400 bacteria, it is increasing at a rate of 60 bacteria per hour.
What is the value of the constant k?
a) 0.15hr−1
b) 0.075hr−1
c) 0.05hr−1
d) 13.3hr−1